Prenatal diagnosis in Coffin-Lowry syndrome demonstrates germinal mosaicism confirmed by mutation analysis

Coffin-Lowry syndrome is a rare X-linked, semi-dominant mental retardation syndrome resulting from mutations of the ribosomal S6 kinase 2 (RSK2) gene. In the present report, a male patient affected with Coffin-Lowry syndrome is shown to have a nonsense mutation of the RSK2 gene. His unaffected mother does not have this mutation in her lymphocytes. In her third pregnancy prenatal diagnosis by mutation analysis has detected gonadal mosaicism. As this is the second report of germinal mosaicism in Coffin-Lowry syndrome, the finding has important implication for genetic counselling. Copyright © 2001 John Wiley & Sons, Ltd.     

Determination of organochlorinated compounds and petroleum hydrocarbons in sediment sample IAEA-408. Results from a world-wide intercalibration exercise

A sediment sample from the intertidal mudflats of the Tagus estuary was prepared, homogenised and distributed globally to laboratories as the IAEA-408 intercomparison material for the analyses of organochlorinated pesticides, PCBs and petroleum hydrocarbons (PHs). A total of 48 laboratories from 36 countries reported their results. The data from participants show that there still remain some difficulties with the accurate determination of organic contaminants such as pesticides and polycyclic aromatic hydrocarbons (PAHs). More consistent interlaboratory results were obtained for PCBs congeners. The final results of this intercomparison exercise enable individual participants to assess their performance and, where necessary, to introduce appropriate modifications in their analytical procedures. Furthermore, as a series of statistical criteria was fulfilled for a number of compounds, the sample IAEA-408 can now be used as a reference material for quality control in the determination of some persistant organic pollutants (POPs) in marine sediment samples.     

Effects of photodegradation of dissolved organic matter on the binding of benzo(a)pyrene

Dissolved organic matter (DOM) in natural waters can bind various organic pollutants, and the affinity of this binding is strongly influenced by the chemical characteristics of the DOM and water pH. This study examined the effects of photochemically induced alteration of the DOM's chemical properties and water pH on the binding of benzo(a)pyrene (BaP). Time- and pH-series of solar-simulated irradiations were performed on a natural water sample and aqueous DOM solutions prepared from aquatic and soil humic substances. The binding affinity of BaP, expressed as a partition coefficient of a compound to DOM, decreased substantially after the DOM samples were irradiated over environmentally relevant radiation doses and pH ranges. The lowering of the pH due to the photoproduction of acidic products often partly offsets the reduction of the binding affinity caused by direct photoalteration of the DOM's chemical structure. The decrease of the binding affinity, after correction for the photoinduced pH change, was positively correlated with the decrease in the molecular weight and the aromaticity of the DOM in the course of irradiation. Increasing O(2) abundance accelerated the decrease of the binding affinity as a result of enhanced DOM photodegradation. Visible light played a more important role in reducing the molecular weight and aromaticity of the DOM than in reducing the content of dissolved organic carbon (DOC) via photoremineralization while the reverse was true for UV radiation, indicating that photochemical reduction of the binding affinity may occur in natural waters at depths greater than UV radiation can reach. A decrease of the affinity of DOM for binding BaP will increase the free dissolved fraction of BaP and thus its availability and toxicity to aquatic organisms. The results from this study may have similar implications for organic pollutants other than BaP.     

Conceptual evolution of the bioeconomy: a bibliometric analysis

Environment, Development and Sustainability - The growing concern over the change in climatic conditions and the management and conservation of biological resources makes it necessary to create...